#include <boost/asio.hpp>
#include <ctime>
#include <functional>
#include <iostream>
#include <memory>
#include <string>

using boost::asio::ip::tcp;

std::string make_daytime_string()
{
    using namespace std; // For time_t, time and ctime;
    time_t now = time(0);
    return ctime(&now);
}

class tcp_connection : public std::enable_shared_from_this<tcp_connection>
{
  public:
    typedef std::shared_ptr<tcp_connection> pointer;

    static pointer create(boost::asio::io_context &io_context) { return pointer(new tcp_connection(io_context)); }

    tcp::socket &socket() { return socket_; }

    void start()
    {
        message_ = make_daytime_string();

        boost::asio::async_write(
            socket_, boost::asio::buffer(message_),
            std::bind(&tcp_connection::handle_write, shared_from_this(), std::placeholders::_1, std::placeholders::_2));
    }

  private:
    tcp_connection(boost::asio::io_context &io_context) : socket_(io_context) {}

    void handle_write(const boost::system::error_code &error, size_t bytes_transferred) {}

    tcp::socket socket_;
    std::string message_;
};

class tcp_server
{
  public:
    tcp_server(boost::asio::io_context &io_context)
        : io_context_(io_context), acceptor_(io_context, tcp::endpoint(tcp::v4(), 5002))
    {
        start_accept();
    }

  private:
    void start_accept()
    {
        tcp_connection::pointer new_connection = tcp_connection::create(io_context_);

        acceptor_.async_accept(new_connection->socket(),
                               std::bind(&tcp_server::handle_accept, this, new_connection, std::placeholders::_1));
    }

    void handle_accept(tcp_connection::pointer new_connection, const boost::system::error_code &error)
    {
        if (!error)
        {
            new_connection->start();
        }

        start_accept();
    }

    boost::asio::io_context &io_context_;
    tcp::acceptor acceptor_;
};

int main()
{
    try
    {
        boost::asio::io_context io_context;
        tcp_server server(io_context);
        io_context.run();
    }
    catch (std::exception &e)
    {
        std::cerr << e.what() << std::endl;
    }

    return 0;
}